110 FXPQ50 PGUM 310801 AFDGUM Area Forecast Discussion National Weather Service Tiyan GU 601 PM ChST Wed Dec 31 2025 .Marianas Synopsis... Satellite imagery shows partly cloudy skies, while radar imagery shows a few isolated showers over the region. Altimetry shows combined seas of 6 to 8 feet to the west of the Marianas, and buoy data shows 5 to 6 foot swells at 8 seconds. && .Discussion... A decaying shear line remains over the Marianas. This is expected to bring scattered showers over night. For the rest of the week a dry trade-wind pattern is expected to return. Then, around the beginning of next week the next shear line anticipated to move close to the Marianas. && .Marine/Surf... Seas are expected to be 5 to 7 feet with a period of 6 to 8 feet for the next few days. Then seas are expected relax a little before the next pulse moves into the region. Near the beginning of next week, another pulse of north swell looks to arrive, potentially bringing a significant increase to sea and surf heights in a short time frame. This may warrant a the small craft advisory (seas of at least 10 feet), high surf advisory (surf of at least 9) and high risk of rip currents statement. Winds are expected to be gentle to moderate through the beginning of next week. && .Eastern Micronesia... The weak circulation found south of Kosrae has weakened since yesterday and has now opened up into a broad, southeast-to-northwest oriented surface trough. Gentle to fresh northeast trade winds that prevail across the region converge along the light to gentle winds to the south of this feature, producing patchy clouds, showers and a few thunderstorms. This is mainly in the southern half of the region, with some patchy showers lingering near southern Kosrae waters tonight. Overall, a fairly dry trade-wind pattern is expected over the next couple days and over the weekend, with showers primarily remaining south of 5N, along a small area of trade-wind convergence. Altimetry shows 5 to 7 feet near Pohnpei and Kosrae and 6 to 8 feet near Majuro. Buoy observations at Pohnpei shows a primary east to northeast trade swell and secondary northerly swell. This pulse of northerly swell looks to peak at 3 to 5 feet around Friday with a longer period of 13 to 15 seconds, which may warrant another issuance of a High Surf Advisory along north-facing reefs for Pohnpei and Kosrae. Additionally, an increase in trade swell on Thursday night or Friday may increase surf to hazardous levels along east-facing reefs of Kosrae. For Majuro, the Wave Run-Up forecast suggests minor inundation along northern and eastern shorelines during times of high tide over the next few days, due to these trends in swells, an increase in wind waves and combined seas, and the influence of the moon cycle (full moon this Friday). Peak high tides look to be closer to Saturday and Sunday, so will continue to monitor to assess any need for a High Surf Advisory and a Coastal Flood Statement for the next few days. && .Western Micronesia... Not much as changed in the overall forecast for the next several days. A series of troughs are generating scattered showers and isolated thunderstorms across Palau and this overall pattern is expected to continue through the weekend, with showers oscillating between isolated and scattered as troughs pass through the republic. As expected, one of these troughs has caused scattered showers to lift northward into Yap Proper this evening, but drier weather should return Thursday as the trough moves off to the west. Similar to Yap, Chuuk is expected to be in a fairly dry trade-wind pattern through the rest and into early next week, with some spotty trade showers moving through the state. Altimetry data and the drifting buoy near Yap suggest seas are still between 5 and 7 feet this evening. An increase in the trade swell, along with the lingering north swell, will boost seas and surf at Chuuk slightly around Thursday night or Friday. Still expecting seas to remain below 10 feet and surf is still not expected to reach hazardous levels of 9 feet along north facing reefs and 12 feet along east facing reefs during this period. Later, a pulse north to northwest swell will impact Palau and Yap this weekend or early next week, causing a notable increasing surf that may reach hazardous levels of 9 feet along north and west facing reefs. This swell is then expected to move into Chuuk, and may cause similar high surf concerns for next week. Light to moderate winds will persist at Yap and Palau over the next several days. Moderate to fresh trade winds at Chuuk will continue through Friday and then drop to gentle to moderate for the weekend. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...None. MP...None. Marianas Waters...None. && $$ Marianas: Bowsher East Micronesia: Cruz West Micronesia: Schank